Electromagnetic cut-out.



No. 665,423. Patented Ian. 8, I901. R. FLEMING.

ELECTROMAGNETIC CUT-OUT.

' (Appli :lti0n fllod Nov. 24, 1899.) (No Model.)

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RICHARD FLEMING, OF LYNN, MASSACHUSETTS, ASSIGNOR TO THE GEN- ERAL ELECTRIC COMPANY, OF NEW YORK.

ELECTROMAGNETIC CUT-OUT.

SPECIFICATION formingpart of Letters Patent No. 665,423, dated January 8, 1901.

Application filed November 24. 1899- Serial No. 788,143. (No model.)

To (LZZ whom, it fluty cancer/2,:

Be it known that I, RICHARD FLEMING, a subject of the Queen of Great Britain, residing at Lynn, county of Essex, State of Massachusetts, have in vented certain new and useful Improvements in Electromagnetic Cut- Outs, (Case No. 960,) of which the following is a specification.

This invention relates to electromagnetic cut-outs. It is particularly adapted for use in what is commonly known as the bridgecontact in a Well-known form of Thomson- Houston arc-lam p,such as described in the patent to Thomson and Rice, No. 370,572, dated September 2'7, 1887. In that type of lamp the carbons are normally held apart, and a series coil, including the bridge-contact,is normally in circuit with the arc-lamp terminals, so that when current is imposed on the circuit the coil acts to draw the carbons together, and when they touch a new circuit is made, including an auxiliary electromagnet, controlling byits armature the bridge-contact, thereby operating the latter and opening the circuit of the series coil, the regulation being effected by a shunt-coil continuously in circuit. The bridge-contact carries a current of considerable voltagefrom siX to nine amperes-and is liable to corrosion by the arc formed at the contacts when opened. Corrosion is prevented by shoeing the contacts at their engaging point with tips of silver. The movable parts of the cut-out are commonly provided with a hinge-joint turning on a riveted pin which holds the two movable contacts in inflexible relationship, and when they are badly alined or bent confines the face of contact to a sin gle point, thereby reducing the time within which the device can act effectively.

The object of my invention is to so improve the construction that the contacts are at all times free to aline with one another and engage over their entire confronting edges and provide a uniform pressure at all points on the edge, also preventing one side from tilting with respect to the other. 1 effect these results by forming a loose hinge-joint between the two parts, which are simply hooked together and free to assume slightly-different relative angles, so that if the parts become bent or warped the spring which draws them together can act to keep the engaging edges in a position of perfect parallelism and contact. This parallelism is further promoted by a particular way of mounting the connecting-spring by fixing its points of attachment to the two parts at a symmetrical position between the two sides where the parts are hooked together.

The construction of the organization is further simplified and cheapened by forming the parts of sheet-metal punchings, thereby securing perfect uniformity in their shape and relationship and conducing to a better action in service.

While my invention is particularly designed for use in connection with Thomson-Houston arc-lamps, as above noted, it may be employed generally in cut-outs where two movable contacts are automatically controlled to open or close an electric circuit.

In the accompanying drawings, which illustrate the invention, Figure 1 is a side elevation of a device embodying my improvements. Fig. 2 is a view at right angles to Fig. 1, showing the parts in end elevation and the supporting-frame in section. Fig. 3 is a perspective view of the bridge-contact.

1 represents a portion of an arc-lamp frame on which the controlling electromagnets and the bridge-contact are supported. The latter is provided with a block of indurated fiber or other heat-resisting insulating material 2, which may be clamped to the frame or projections thereof by means of set-screws, as indicated in Figs. 1 and 2. The fiber is slotted vertically, as indicated, to permit an upand-down adjustment with relation to the magnets, and thereby permit the armature 3 to be adjusted relatively to the poles of the magnet. On the fiber-support is fastened one member of the bridge-contact, (shown at 4.) This is formed of a punching from sheet metal, and may be of German silver, brass, or other suitable material. It is provided with a rightangled bond, as indicated in Fig. 2, forming a face against which the fiber block may hear when the parts are drawn together by a set screw 5. The two ends are curved outwardly, as indicated in the figure, the bottom of the rear end being bent at right angles and provided with two hooks 6 6, which pass through corresponding notches in the movable member, forming a loose hinge-joint, in which the parts may tilt slightly with respect to one an other to accommodate the engaging edges of the contacts and permit a condition of true parallelism therewith. Symmetrically related with the two points at which the hingejoint is provided is a helical spring 7, the ends of which are fastened to the fixed and movable members of the cut-out. Connection is made by punching small holes in the blanks, through which the ends of the spring are carried and bent in the form of an eye, so as to maintain the spring distended. The contacts are shod with U-shaped strips of silver 8 8, secured in place by hard solder or other satisfactory method of promoting good electric contact. The front end of the movable memher is provided with a bend 9 to facilitate setting it in position on the armature, to which it is connected. It is insulated therefrom by asbestos or other fireproof washers, as indicated in Fig. 2, and the strip on which the movable contact is mounted is similarly insulated, being held to the armature by the set-screw, as indicated in Fig. 2, to which access for assembling or taking the pieces apart may be had through a hole 10, punched in the fixed member of the cut-out in its process of formation. Circuit-terminals are connected to the two contacts, as indicated, one being connected to the fixed member 4 and the other to the rear end of the plate which carries the movable contact 8. The magnet 11, which actuates the contacts, is in an independent circuit closed through the lamp-carbons, so that the contact is held open by the magnet as long as the lamp burns.

Several advantages result from a device as constructed in accordance with the description hereinabove set forth. XVith a riveted joint between the fixed and movable members as commonly constructed there is little or no flexibility at the silver contacts, a slight side twist causing the contacts to touch only at one point instead of along the entire edge. The looseness afforded by my present construction renders the two parts perfectly flexible in all directions, and the symmetrical relation of the tensionspring keeps them in perfect parallelism. The tension-spring eommonly provided, placed at the hinge, prod uces an uneven pressure on the sides of the frame, which tends to twist the contacts out of alinement.

Another advantage of the present construction is in the method of assembling, which is more rapid, since there is no riveted joint, permitting the parts to be easily taken apart and put together.

What I claim as new, and desire to secure by Letters Patent of the United States, is

l. A cut-out formed of fixed and movable contacts insulated from one another and provided with circuit connections, the parts on which they are mounted being connected together by a loose joint permitting relative yielding of the contacting edges, and a spring holding the parts in engagement and symmetrically related with respect to the points of connection.

2. A cut-out comprising a fixed and a movable member yieldingly connected and engaging one another along the confronting edges, electrically operated means for separating the members, and a hook-joint between the two members.

An electromagnetic cut-out con'lprising a fixed and a movable contact insulated from one another, connections with an electric circuit, a hinge-joint formed of sheet metal hav ing a tongue-and-groove connection, and an eleetromagnet controlling the operation of the contacts.

l. A cut-out comprising a fixed and a movable contact, the tixed and movable members being formed of sheet metal, one being provided with a plurality of punched tongues engaging corresponding slots in the other so as to form a loose hinge-joint, a spring connecting the parts and having its connecting-points symmetrically related with respect to the pivotal connections, and electrically-operated means for operating the cutout.

5. An electromagi'ietic cut-out comprising an insulating-support for the parts, the latter being formed with sheet metal shed with silver at their engaging edges, the fixed member being provided with a bend or shoulder to abut against the insulating-support, means for fastening the two together, the two parts being provided with a tongue-and-groove connection, a controlling-spring, an insulated contact, an armature connected to the movable member, and an electromagnet for controlling the engagement of the contacts.

6. An electromagnetic cut-out comprising an insulating-support for the parts, the latter being formed of sheet metal and provided with non-oxidizing contacts, a loose hookjoint between the parts at their rear ends, a controlling-spring between the two parts, an armature secured to the movable part between the joint and the contacts, a set-screw beneath the upper part and an opening in the latter for access to the set-screw.

In witness whereof I have hereunto set my hand this 21st day of November, 1899.

RICHARD FLEMING.

Witnesses:

DUG-ALD McKILLor, Guns. B. BEri-IUNE. 

